I can only relate what I have done. I have had Sky for years so now have three boxes standard Sky, then Sky+ and finally Sky+HD of the three boxes to use them without subscription the original box is best as it allows one to program it to auto change program the latter ones after they included a hard drive don't have this feature. Also the hard drive keeps kicking in even though you can't use it.
I also have a range of free to air boxes. It seems these are different to freesat the free to air gives now and next only with electronic program guide but freesat is same as sky with program guide. The disadvantage with freesat is setting them to record is purely by time, no series link and no auto correct when program times move. However with the cheap boxes on stand-by can't actually measure the power used, the sky box on stand-by can still be using 20 watt as to be able to auto correct to program changes the LNB must be powered.
There are also some advantages with the free to air box. You can set the order of programs so mine is set BBC1, BBC2, BBC3, BBC4, ITV1, ITV1+1, ITV2 etc. I find having the Plus 1 next to standard time a real advantage when called away no hunting for the plus 1 you can also delete all programs you can't watch or don't want to watch like all the shopping and porn channels.
The last free to air I bought was Iceweasel from Maplin. Rather a disappointment I thought it would work like my old blueray box and allow me to watch U-tube, and BBC catch-up etc. However as far as internet goes only got weather. Also a real pain to program my Flipper remote control to work it. However on the plus side the unit will take any USB stick or hard drive and allow both recording and viewing I think MP4 format so you can also watch recordings on computer etc. My daughter got one which although it would record was in a special format and it actually re-formatted the drive or stick be aware of that. Anyway it's for my mother and what I found there are more HD channels I can watch on the Iceweasel from Maplin than I can watch on my Sky HD+ box even with the subscription.
In the main anything on freeview is also on free to air with a few exceptions UKTV is the odd one out you can't watch UKGold, and Dave on free to air. However there are many programs which are not on freeview which are on free to air. Films for men for example.
Before getting the Iceweasel from Maplin we went to Curries and they had what seemed some really good catch up TV boxes I was really impressed with the demo. However when I got home it would not do anything until I entered all my bank card details which there was no way I was doing. So it went back. It would seem many of the catch-up boxes are the same, that's how I ended up with the Iceweasel from Maplin.
Freeview is really a pain. I still have my mother TV an LG set-up to watch freeview, and about once a month freeveiw change their programs, when they do this the TV displays a message that it needs re-tuning even when set to watch the free to air box, and I have to go down yet again to re-program the freeview 12 miles just because they have changed a channel we likely never watch anyway. At home freeview has been kicked to touch because of this. I have no terrestrial aerial it's such a pain it seems nearly once a week I need to re-program at one point it was daily. Maybe because I live on a hill and can receive four or more masts the problem is higher?
My wife likes Universal and Encore so we still have the lowest sky package. However in my bedroom and in spare bedroom we have free to air boxes so I can watch an alternative channel. I hate any program which has a bong bong when it swaps scene, I refuse to watch them. What I have noticed is Plus 1 free to air seems to work most of the time. But Plus 1 on freeview only works at certain times of the day.
With the old sky box used for mother I have a flipper remote control. These are for people with alsimizers and they with slider shut only have 6 buttons on/off, mute, vol up, vol down, prog up, prog down. I find with the sky box without subscription these are great as you can program in 25 favourites in the order you want. So ITV3 then ITV3+1 etc. So no need to wade through programs you can't get.
With the Iceweasel I have got rid of all the useless channels and I have around 75 channels to watch. If you remove all the useless channels from freeview one is left with about 25 not that it allows you to do that. So to my mind you already have a satellite dish so it's free to air or freesat depending if you want the electronic program guide.